New Zealand can be used as an evidence that the proposal to ignore biogeographic origin when addressing threats from harmful species is fundamentally flawed. Marked differences exist in the composition of alien and native plant functional groups, with few annuals, succulents or nitrogen-fixing legumes in the native flora.
Whereas these aliens have benefited from the rapid anthropogenic transformation of the landscape, this is not the case for most endemic native species. Rather than ignore the differences between natives and aliens, researchers urgently need to understand the success of the latter as a guide to how species might adapt or evolve in response to the future conditions of the 21st century.